Blowout preventer test system

ABSTRACT

The present disclosure provides a cooling system and method for a reciprocating mandrel in a blowout preventer test system that provides coolant to the mandrel through a majority of its stroke. The system includes an inner coolant tube and an outer coolant tube, with both tubes inserted into a mandrel inner bore. The inner coolant tube is fixed in position on a base and not attached to the mandrel. The outer coolant tube is fixed in position and attached to the mandrel. The outer coolant tube slidably and optionally sealingly engages the inner coolant tube throughout the mandrel stroke. Coolant can flow through the base, upward through an inner volume of the inner coolant tube, and into an inner volume of the outer coolant tube and out of coolant openings in the outer coolant tube to flow on the inner bore surfaces of the mandrel to cool the mandrel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/117,980, filed Feb. 19, 2015.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

Field of the Invention

The disclosure generally relates to the oil field equipment.Specifically, the disclosure relates to the test equipment for blowoutpreventers.

Description of the Related Art

With the tragic incident of an offshore explosion caused when a safetyblowout preventer (“BOP”) failed to close a subsea oil well after a gasleak, more engineering designing and testing of blowout preventers arebeing done by those in the oil field industry. A fatigue test simulateswell tubing being inserted through the BOP to determine whether the BOPcan hold pressure over its expected life. A known BOP test system isshown in FIG. 1. The BOP test system 102 includes a reservoir 104 ofhydraulic fluid with supply lines 116 connected to pumps 106. The pumps106 supply pressurized hydraulic fluid to a high pressure filter 120through supply lines 118 and then to a hydraulic control valve 108. Thecontrol valve 108 controls hydraulic fluid flow into and out of ahydraulic cylinder 110. A heat exchanger 122 cools the hydraulic fluidin the reservoir. The hydraulic cylinder 110 repetitiously raises andlowers a hollow mandrel through internal BOP seals (not shown) to testthe BOP design and integrity. The large number of quick repetitionsconducted for the test causes friction that causes heat on the seals,which is not experienced in the field. To better simulate fieldconditions, the seals are cooled by a fluid. A cooling system with acoolant reservoir, pump, and heat exchanger is attached to a lowerportion of the BOP test system. Coolant enters through a flanged basethat is attached to a chamber below the BOP and flows upward through acooling tube that is smaller in diameter than the mandrel insidediameter. As the mandrel raises and lowers through the BOP seals, thefixed position inner tube sprays or otherwise flows the coolant on theinside of the mandrel. However, the inner tube only flows the coolant tothe particular surface of the mandrel that is adjacent the inner tube ata particular time during that portion of the mandrel stroke as themandrel is raised and lowered. The inner tube is not able to flow freshcoolant to any mandrel inside surface that is above the inner tube forother portions of the stroke. Proportionately, at least one-half of themandrel is therefore not cooled with flowing coolant during a given fullstroke of the mandrel.

There remains then a need to provide a better cooling system for themandrel during a greater portion the mandrel stroke.

BRIEF SUMMARY OF THE INVENTION

The present disclosure provides a cooling system for a reciprocatingmandrel in a blowout preventer test system that provides coolant to themandrel through a majority of its stroke. The system includes an innercoolant tube and an outer coolant tube, with both tubes inserted into aninner bore of the mandrel. The inner coolant tube is fixed in positionon a base and not attached to the mandrel. The outer coolant tube isfixed in position and attached to the mandrel. The outer coolant tube isnot fixedly attached to the inner coolant tube, but slidably andoptionally sealingly engages the inner coolant tube throughout themandrel stroke. Coolant can flow through the base, upward through aninner volume of the inner coolant tube, and into an inner volume of theouter coolant tube and out of coolant openings in the outer coolant tubeto flow on the inner bore surfaces of the mandrel to cool the mandrel.Because the outer coolant tube can remain coupled to the mandrel in anupper portion of the mandrel inner bore during the stroke and continueto receive coolant from the fixed inner coolant tube, the coolant canflow to the inner bore surfaces substantially throughout the entirestroke.

The disclosure provides a blowout preventer (“BOP”) test system,comprising: an actuator fluid source; an actuator fluid pump fluidiclycoupled to the actuator fluid source; an actuator valve fluidiclycoupled to the actuator fluid pump; an actuator fluidicly coupled to theactuator valve; a test stand having first chamber and coupled to theactuator; an inner coolant tube coupled to the test stand and disposedat least partially in the first chamber; an outer coolant tube slidablycoupled with the inner coolant tube and having coolant openings in aportion of a top half of the outer coolant tube; a mandrel coupled tothe actuator and configured to at least partially pass through the BOP,the mandrel having an inner cavity configured to allow the outer coolanttube to be disposed therein with the outer coolant tube coupled to themandrel and the coolant openings of the outer coolant tube beingconfigured to deliver coolant to a portion of a top half of the innercavity of the mandrel independent of a position of the mandrel relativeto the inner coolant tube during a stroke of the mandrel; a BOP coolantoutlet fluidicly coupled with the first chamber; a pressure controlvalve fluidicly coupled to the BOP coolant outlet; a coolant sourcefluidicly coupled to the pressure control valve; a coolant pumpfluidicly coupled to the coolant source; a heat exchanger fluidiclycoupled to the coolant pump; and a BOP coolant inlet fluidicly coupledto the heat exchanger and to the inner coolant tube.

The disclosure provides a method of testing a BOP with the BOP testsystem comprising: flowing actuator fluid from the actuator fluid sourceto the actuator fluid pump; pumping the actuator fluid to the actuatorvalve; controlling the actuator fluid flow through the actuator valve tothe actuator; reciprocally moving the mandrel by the actuator through aBOP mounted on the test stand; generating heat from the reciprocalmovement of the mandrel through the BOP; flowing coolant from thecoolant source to the coolant pump, through the heat exchanger, throughthe BOP coolant inlet, through the inner coolant tube, through the outercoolant tube, and out of the coolant openings in the outer coolant tubeto inner surfaces of the top half of the mandrel inner cavityindependent of a position of the mandrel relative to the inner coolanttube during a stroke of the mandrel.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a schematic of a known BOP test system.

FIG. 2A is a schematic diagram of an improved BOP test system.

FIG. 2B is a schematic diagram of an internal portion of the BOP testsystem of FIG. 2A with improved cooling.

FIG. 3 is a schematic of an exemplary hollow mandrel having a uniformoutside surface.

FIG. 4 is a schematic of an exemplary hollow mandrel having anon-uniform outside surface.

FIG. 5 is a schematic of an upper portion of the mandrels of FIGS. 3 and4 with an internally mounted outer coolant tube in the upper portion ofthe mandrel.

FIG. 6 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube.

FIG. 7 is a schematic detail portion of an interaction between the innercoolant tube slidably engaged with the outer coolant tube with anoptional seal therebetween.

FIG. 8 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube at a lowerportion of a stroke of the mandrel.

FIG. 9 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube at anintermediate portion of the mandrel stroke.

FIG. 10 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube at an upperportion of the mandrel stroke.

DETAILED DESCRIPTION

The Figures described above and the written description of specificstructures and functions below are not presented to limit the scope ofwhat Applicant has invented or the scope of the appended claims. Rather,the Figures and written description are provided to teach any personskilled in the art to make and use the inventions for which patentprotection is sought. Those skilled in the art will appreciate that notall features of a commercial embodiment of the inventions are describedor shown for the sake of clarity and understanding. Persons of skill inthis art will also appreciate that the development of an actualcommercial embodiment incorporating aspects of the present disclosurewill require numerous implementation-specific decisions to achieve thedeveloper's ultimate goal for the commercial embodiment. Suchimplementation-specific decisions may include, and likely are notlimited to, compliance with system-related, business-related,government-related and other constraints, which may vary by specificimplementation, location and from time to time. While a developer'sefforts might be complex and time-consuming in an absolute sense, suchefforts would be, nevertheless, a routine undertaking for those ofordinary skill in this art having benefit of this disclosure. It must beunderstood that the inventions disclosed and taught herein aresusceptible to numerous and various modifications and alternative forms.The use of a singular term, such as, but not limited to, “a,” is notintended as limiting of the number of items. Also, the use of relationalterms, such as, but not limited to, “top,” “bottom,” “left,” “right,”“upper,” “lower,” “down,” “up,” “side,” and the like are used in thewritten description for clarity in specific reference to the Figures andare not intended to limit the scope of the invention or the appendedclaims. Where appropriate, one or more elements may have been labeledwith an “A” or “B” to designate various members of a given class of anelement. When referring generally to such elements, the number withoutthe letter can be used. Further, such designations do not limit thenumber of members that can be used for that function.

The present disclosure provides a cooling system for a reciprocatingmandrel in a blowout preventer test system that provides coolant to themandrel through a majority of its stroke. The system includes an innercoolant tube and an outer coolant tube, with both tubes inserted into aninner bore of the mandrel. The inner coolant tube is fixed in positionon a base and not attached to the mandrel. The outer coolant tube isfixed in position and attached to the mandrel. The outer coolant tube isnot fixedly attached to the inner coolant tube, but slidably andoptionally sealingly engages the inner coolant tube throughout themandrel stroke. Coolant can flow through the base, upward through aninner volume of the inner coolant tube, and into an inner volume of theouter coolant tube and out of coolant openings in the outer coolant tubeto flow on the inner bore surfaces of the mandrel to cool the mandrel.Because the outer coolant tube can remain coupled to the mandrel in anupper portion of the mandrel inner bore, the coolant can flow to theinner bore surfaces substantially throughout the entire stroke.

FIG. 2A is a schematic diagram of an improved BOP test system. FIG. 2Bis a schematic diagram of an internal portion of the BOP test system ofFIG. 2A with improved cooling. The figures will be described inconjunction with each other. The exemplary BOP test system 2 generallyincludes an actuator fluid source 4, such as a reservoir or othercontainer. An actuator fluid pump 6 is fluidicly coupled to the actuatorfluid source through a supply line 48 to the pump. A filter 52, such asa high pressure filter, is fluidicly coupled to the pump 6, such asthrough a supply line 50 to the filter. An actuator valve 8 is fluidiclycoupled to the filter 52 through further supply lines. For purposesherein, the term “line” is broadly used to include tubing, hosing,ports, and other fluid channels for transferring fluids from onecomponent to another. An actuator 10, such as a hydraulic or pneumaticcylinder, is fluidicly coupled to the actuator valve 8. Further, theactuator can be other components that can move linearly, including rackand pinion, linear actuators, and other devices. (If a corollary systemis based on electrical components, then the analogous components wouldbe considered as being encompassed within the components describedherein. For example, a pump would include a generator, fluid wouldinclude electrical flow of electrons as energy, fluid lines wouldinclude electrical lines, a valve would include a switch, and so forth.)A return line is coupled between the actuator 10 and the valve 8. Thus,fluids can be directed through the valve 8 through one line to theactuator 10, moving the actuator in one direction, and flow back to thevalve through the other line. For a reverse direction, the fluid can besupplied from the valve and returned to the valve in the opposite linesto move the actuator in the reverse direction. The valve 8 can returnfluid back to the actuator fluid source 4 through a return line 46. Aheat exchanger 44 can be coupled in a flow circuit to receive flowthrough the return line 46 or fluid in the actuator fluid source 4, coolthe fluid, and then return the fluid back to the actuator fluid source4.

A BOP test stand 16 can form the structure on which a BOP 14 can beinstalled thereon. The BOP test stand 16 can include a stub 18 thatforms a mounting connection surface for sealingly coupling with a firstchamber 20. The first chamber 20 can include components, such as coolanttubes 40 and 72 described herein, with a port 38 to supply fluid to thecoolant tubes. The BOP 14 to be tested can be mounted on the firstchamber 20, for example, using standard flanged connections. In at leastone exemplary embodiment, a second chamber 24 can be mounted above theBOP 14 and can be used to mount the actuator 10 described above. A BOPcontrol system 54 can be coupled to the BOP 14 for controlling theactuation of the BOP in a customary manner known to those with ordinaryskill in the art. The BOP 14 and the BOP control system 54 can form aBOP assembly 12.

The actuator 10 can move a mandrel 60, described below, reciprocallythrough internal seals of the BOP 14. The reciprocal movement generatesfrictional heat. Therefore, the mandrel 60 and perhaps surroundingcomponents can be cooled using a coolant flow path. Coolant can flowthrough a coolant system that is fluidicly coupled to the first chamber20 and the coolant tubes 40 and 72 therein. In at least one embodiment,the first chamber 20 is pressurized. The coolant is circulated thereinfor cooling the mandrel 60 and then exits the first chamber 20. In atleast one embodiment, the coolant can be cooled and recirculated back tothe first chamber and the coolant tubes. Specifically, in at least oneembodiment, coolant in a coolant source 32, such as a reservoir, isprovided to the coolant pump 34. The coolant pump 34 pressurizes thecoolant and the coolant flows through a heat exchanger 36 for coolingthe coolant. The coolant can flow through one or more lines to a BOPinlet 38 in the stub 18. The stub 18 can be fluidicly coupled to aninside volume of an inner coolant tube 40. The inner coolant tube 40allows the coolant to flow therethrough and exit through one or moreopenings, such as a coolant outlet 42 in the top of the inner coolanttube 40. An outer coolant tube 72 surrounds the outer periphery of theinner coolant tube 40 and receives the coolant from the outlet on theinner coolant tube 40. In at least one embodiment, the outer coolanttube 72 is slidably engaged over the outer periphery of the innercoolant tube 40. The outer tube 72 can be coupled within the innercavity of the mandrel 60. The mandrel in turn can be coupled to theactuator 10. As the actuator 10 reciprocates the mandrel 60, the outercoolant tube 72 moves with the mandrel 60 and the outer tube 72 slidesup and down over the inner coolant tube 40. The outer coolant tube 72includes one or more coolant openings disposed in at least the top halfof the outer coolant tube to allow the coolant to flow to the top halfof the inner cavity of the mandrel to cool the mandrel independent of aposition of the mandrel relative to the inner coolant tube during astroke of the mandrel.

After the coolant flows to the surfaces of the inner cavity of themandrel, the coolant exits an annulus between the surface of the innercavity and the outer surface of the outer coolant tube 72 and flows intothe first chamber 20. The coolant is pressurized in the chamber 20 bythe inflow of the coolant from the outer coolant tube 72 and can exitthe first chamber 20 through a BOP coolant discharge 26. The pressure inthe chamber 20 can be controlled by a pressure control valve 30 that, inat least one embodiment, can be coupled to the BOP coolant discharge 26.The coolant can flow through the pressure control valve 30 back into thecoolant source 32 and/or to the pump 34 and then through the heatexchanger 36 with circulation back to the first chamber 20 and the innercoolant tube 40 therein.

FIG. 3 is a schematic of an exemplary hollow mandrel having a uniformoutside surface. The mandrel 60A has a substantially uniform outersurface 68. Such a surface could represent an outer surface of a conduitor tubing component used in a drill string that is inserted through aBOP in drilling and other operations in the field. The mandrel 60A canalso include an inner cavity 62 that forms a hollow portion in theinternal volume of the mandrel. The inner cavity can be used to insertthe outer coolant tube described herein. The mandrel 60A furtherincludes a coupler 64 that, in the exemplary embodiment, may alsoinclude a coupler opening 66. The coupler 64 can be used to couple themandrel 60A with the actuator 10.

FIG. 4 is a schematic of an exemplary hollow mandrel having anon-uniform outside surface. Another exemplary mandrel 60B includes anon-uniform outer surface 70 having an expanded portion which mayinclude one or more tapers. The expanded portion can simulate tooljoints and other enlarged portions of a typical drill string that wouldpass through a BOP in the field. In a similar fashion, the mandrel 60Bcan include a coupler 64 with a coupler opening 66. These and otherembodiments of mandrels will be generally referred to as mandrel 60.

FIG. 5 is a schematic of an upper portion of the mandrels of FIGS. 3 and4 with an internally mounted outer coolant tube in the upper portion ofthe mandrel. The mandrel 60 with a coupler 64 is coupled with the outercoolant tube 72. In at least one embodiment, the coupling can occur bythe outer coolant tube 72 being inserted into the inner cavity 62. A pinopening 76 in the outer coolant tube 72 can be aligned with a pinopening 78 in the mandrel and a pin 80 can be inserted through the pinopenings 78 and 80 to couple the mandrel with the outer coolant tube.Thus, the outer coolant tube 72 is longitudinal fixably coupled with themandrel 60. Other forms of coupling can occur, including rotationally.The outer coolant tube 72 generally will include one or more coolantopenings 82 in the outer coolant tube to allow coolant that is receivedfrom the inner coolant tube to exit the outer coolant tube and flow tothe surfaces of the inner cavity 62 of the mandrel 60. In at least oneembodiment, the coolant openings 82 can include one or more coolantopenings 82A in a sidewall of the coolant tube 72 and may be spacedaround the periphery of the coolant tube. Further, one or more coolantopenings 82B can be formed at the end 74 of the outer coolant tube 72,in addition to, or in lieu of the coolant openings 82A.

FIG. 6 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube. The assemblyinside the first chamber 20, shown in FIG. 2A, generally includes thecomponents shown in FIG. 6. As described above, the stub 18 can includea BOP coolant inlet 38 that is fluidicly coupled to the inner coolanttube 40. The outer coolant tube 72 can be slidably engaged with theinner coolant tube 40. The outer coolant tube 72 can be longitudinallycoupled with the mandrel 60, such as by using a pin 80 or other couplingdevice.

FIG. 7 is a schematic detail portion of an interaction between the innercoolant tube slidably engaged with the outer coolant tube with anoptional seal therebetween. The outer coolant tube 72 can be slidablyengaged with the inner coolant tube 40, as described above. Tofacilitate coolant flow through the sliding engagement, a sliding seal86 can be disposed in an annulus between the outer coolant tube 72 andthe inner coolant tube 40. Thus, as the outer coolant tube 72 slidesalong the outer surface of the inner coolant tube 40, the seal 86 canreduce leakage along the sliding engagement.

FIG. 8 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube at a lowerportion of a stroke of the mandrel. When the actuator 10 lowers themandrel 60 through the BOP 14, described in FIGS. 2A and 2B, the outercoolant tube 72 that is coupled with the mandrel 60 can be lowered to alow point of the stroke over the inner coolant tube 40. The coolant thatflows through the BOP coolant inlet 38 can flow through the stub 18 andup through the inner coolant tube 40. The coolant flowing through theinner coolant tube 40 can flow into the outer coolant tube 72 and exitthe coolant openings 82 in the outer coolant tube 72 and flow onto thesurfaces of the inner cavity 62 on the mandrel 60. The coolant can flowdownward and exit the annulus between inner cavity 62 and the outercoolant tube 72 and flow into the chamber 20 described in FIGS. 2A and2B.

FIG. 9 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube at anintermediate portion of the mandrel stroke. As the mandrel 60 is liftedby the actuator 10 to an intermediate position of the stroke, the outercoolant tube 72 is lifted with the mandrel 60. Because the inner coolanttube 40 is fixably attached to the stub 18 of the test stand 16, thedistance between the top of the outer coolant tube 72 and the bottom ofthe inner coolant tube 40 increases. However, the relative positionbetween the mandrel 60 and the outer coolant tube 72 does not change.The coolant flow exiting the outer coolant tube remains in a similarposition that is in at least a top half of the inner cavity 62 of themandrel 60, and is independent of the position of the mandrel relativeto the inner coolant tube during the stroke of the mandrel.

FIG. 10 is a schematic of the base, inner coolant tube, outer coolanttube, and mandrel attached with the outer coolant tube at an upperportion of the mandrel stroke. As the actuator 10 raises the mandrel 60to a top portion of the mandrel stroke, the outer coolant tube 72 isfully raised with the mandrel 60 independent of the inner coolant tube40. The outer coolant tube 72 is still fluidicly coupled with the innercoolant tube 40, but the outer coolant tube has not changed itslongitudinal position with the mandrel 60. Thus, coolant through theinner coolant tube 40 going into the outer coolant tube 72 and out ofthe coolant opening 82 can still flow onto the surfaces of the mandrelinner cavity 62 in a top half portion of the mandrel inner cavity 62,and then flow out of the annulus between the inner cavity 62 and theouter coolant tube 72. Thus, at the different positions of the mandrelduring the mandrel stroke, the mandrel can be cooled with coolantflowing out to at least a top half of the mandrel inner cavity andgenerally downward along the remaining surfaces of the inner cavity asthe coolant flows along the annulus between the inner cavity 62 and theouter coolant tube 72. Advantageously, the coolant can exit a topportion of the outer coolant tube 72 toward a topmost portion of theinner cavity 62 to help maximize cooling on the inner surfaces of themandrel inner cavity. The coolant exiting the annulus of the innercavity 62 and outer coolant tube 72 can flow into the chamber 20 andthen out of the chamber 20 to be cooled and recirculated as describedabove.

Other and further embodiments utilizing one or more aspects of theinvention described above can be devised without departing from thespirit of Applicant's invention. For example, other types of mandrels,actuators, pumps, reservoirs, coolant tubes, and test stands can beused, as well as other variations can occur in keeping within the scopeof the claims.

Further, the various methods and embodiments of the system can beincluded in combination with each other to produce variations of thedisclosed methods and embodiments. Discussion of singular elements caninclude plural elements and vice-versa. References to at least one itemmay include one or more items. Also, various aspects of the embodimentscould be used in conjunction with each other to accomplish theunderstood goals of the disclosure. Unless the context requiresotherwise, the word “comprise” or variations such as “comprises” or“comprising,” should be understood to imply the inclusion of at leastthe stated element or step or group of elements or steps or equivalentsthereof, and not the exclusion of a greater numerical quantity or anyother element or step or group of elements or steps or equivalentsthereof. The device or system may be used in a number of directions andorientations. The term “coupled,” “coupling,” “coupler,” and like termsare used broadly herein and may include any method or device forsecuring, binding, bonding, fastening, attaching, joining, insertingtherein, forming thereon or therein, communicating, or otherwiseassociating, for example, mechanically, magnetically, electrically,chemically, operably, directly or indirectly with intermediate elements,one or more pieces of members together and may further include withoutlimitation integrally forming one functional member with another in aunity fashion. The coupling may occur in any direction, includingrotationally.

The order of steps can occur in a variety of sequences unless otherwisespecifically limited. The various steps described herein can be combinedwith other steps, interlineated with the stated steps, and/or split intomultiple steps. Similarly, elements have been described functionally andcan be embodied as separate components or can be combined intocomponents having multiple functions.

The invention has been described in the context of preferred and otherembodiments and not every embodiment of the invention has beendescribed. Obvious modifications and alterations to the describedembodiments are available to those of ordinary skill in the art. Thedisclosed and undisclosed embodiments are not intended to limit orrestrict the scope or applicability of the invention conceived of by theApplicant, but rather, in conformity with the patent laws, Applicantintends to protect fully all such modifications and improvements thatcome within the scope or range of equivalents of the following claims.

What is claimed is:
 1. A blowout preventer (“BOP”) test system,comprising: an actuator fluid source; an actuator fluid pump fluidiclycoupled to the actuator fluid source; an actuator valve fluidiclycoupled to the actuator fluid pump; an actuator fluidicly coupled to theactuator valve; a test stand having first chamber and coupled to theactuator; an inner coolant tube coupled to the test stand and disposedat least partially in the first chamber; an outer coolant tube slidablycoupled with the inner coolant tube and having one or more coolantopenings in a portion of a top half of the outer coolant tube; a mandrelcoupled to the actuator and configured to at least partially passthrough the BOP, the mandrel having an inner cavity configured to allowthe outer coolant tube to be disposed therein with the outer coolanttube coupled to the mandrel and the coolant openings of the outercoolant tube being configured to deliver coolant to a portion of a tophalf of the inner cavity of the mandrel independent of a position of themandrel relative to the inner coolant tube during a stroke of themandrel; a BOP coolant outlet fluidicly coupled with the first chamber;a pressure control valve fluidicly coupled to the BOP coolant outlet; acoolant source fluidicly coupled to the pressure control valve; acoolant pump fluidicly coupled to the coolant source; a heat exchangerfluidicly coupled to the coolant pump; and a BOP coolant inlet fluidiclycoupled to the heat exchanger and to the inner coolant tube.
 2. Thesystem of claim 1, wherein combination of the inner coolant tube, theouter coolant tube, and the coupling of the outer coolant tube with themandrel is configured to deliver fluid to the top half portion of themandrel inner cavity during more than one-half of a stroke of themandrel in the BOP.
 3. The system of claim 1, further comprising theouter coolant tube having an outlet at the top of the outer coolanttube.
 4. The system of claim 1, wherein the outer coolant tube isremovably coupled with the mandrel.
 5. The system of claim 1, furthercomprising a seal disposed between an outside periphery of the innercoolant tube and an inside periphery of the outer coolant tube.
 6. Thesystem of claim 1, further comprising a BOP mounted on the test standand configured to allow the mandrel to reciprocally pass therethrough.7. A method of testing a blowout preventer with a test system,comprising a blowout preventer (“BOP”) test system, the test systemcomprising: an actuator fluid source; an actuator fluid pump fluidiclycoupled to the actuator fluid source; an actuator valve fluidiclycoupled to the actuator fluid pump; an actuator fluidicly coupled to theactuator valve; a test stand having first chamber and coupled to theactuator; an inner coolant tube coupled to the test stand and disposedat least partially in the first chamber; an outer coolant tube slidablycoupled with the inner coolant tube and having coolant openings in aportion of a top half of the outer coolant tube; a mandrel coupled tothe actuator and configured to at least partially pass through the BOP,the mandrel having an inner cavity configured to allow the outer coolanttube to be disposed therein with the outer coolant tube coupled to themandrel and the coolant openings of the outer coolant tube beingconfigured to deliver coolant to a portion of a top half of the innercavity of the mandrel; a BOP coolant outlet fluidicly coupled with thefirst chamber; a pressure control valve fluidicly coupled to the BOPcoolant outlet; a coolant source fluidicly coupled to the pressurecontrol valve; a coolant pump fluidicly coupled to the coolant source; aheat exchanger fluidicly coupled to the coolant pump; and a BOP coolantinlet fluidicly coupled to the heat exchanger and to the inner coolanttube, the method comprising: flowing actuator fluid from the actuatorfluid source to the actuator fluid pump; pumping the actuator fluid tothe actuator valve; controlling the actuator fluid flow through theactuator valve to the actuator; reciprocally moving the mandrel by theactuator through a BOP mounted on the test stand; generating heat fromthe reciprocal movement of the mandrel through the BOP; flowing coolantfrom the coolant source to the coolant pump, through the heat exchanger,through the BOP coolant inlet, through the inner coolant tube, throughthe outer coolant tube, and out of the coolant openings in the outercoolant tube to inner surfaces of the top half of the mandrel innercavity independent of a position of the mandrel relative to the innercoolant tube during a stroke of the mandrel.
 8. The method of claim 7,further comprising flowing the coolant from the inner surface of the tophalf of the mandrel inner cavity to a pressure control valve.
 9. Themethod of claim 8, further comprising flowing the coolant through theheat exchanger and flowing the coolant to the first chamber having theinner coolant tube.